inoculant
/ɪˈnɑkjələnt/
noun
- A substance (such as a vaccine or a serum) introduced into the body to produce immunity against a disease.
- The doctor administered an inoculant to protect the child against measles.
- Farmers sometimes use an inoculant to help crops resist certain bacteria.
- Researchers are developing a new inoculant for the flu virus.